Not at all... although in practice when shifting to the next 'higher' gear, for example, you generally shift to the 'highest' gear by ringing up (34t to 50t) before backing down by shifting to a bigger cog (e.g., 16t to 22t). But, it's done in a continuous manner. Modern electronic shifting systems like Di2 and EPS make the technique even easier. The only real 'trick' involved is just to know what gear you are in.